Optimizations and more documentation of SkShadowShader

samplecode/SampleShadowing.cpp

Index: samplecode/SampleShadowing.cpp
diff --git a/samplecode/SampleShadowing.cpp b/samplecode/SampleShadowing.cpp
index 4892f9c27df5c97eb27bd38175a2f59ac5082aac..529a6dd7cd15178ad77997e3fd87197d4902c5f3 100644
--- a/samplecode/SampleShadowing.cpp
+++ b/samplecode/SampleShadowing.cpp
@@ -53,7 +53,7 @@ public:
 
         fShadowParams.fShadowRadius = 4.0f;
         fShadowParams.fBiasingConstant = 0.3f;
-        fShadowParams.fMinVariance = 1024;
+        fShadowParams.fMinVariance = 0.015625;

[jvanverth1, 2016/08/29 18:30:14]

It's not clear to me why this is now 1/64.

[vjiaoblack, 2016/08/29 19:45:21]

I'll put the tranform in later.

It was because I use variance in a 0 - 1 space instead of 0 - 65536 space in the
shader now

         fShadowParams.fType = SkShadowParams::kVariance_ShadowType;
     }